Abstract
Vascular access is one of the leading causes of mobilization of financial resources in health systems for people with chronic kidney disease on hemodialysis. Physical examination of the arteriovenous fistula (AVF) has demonstrated its effectiveness in identifying complications. We decided to evaluate the influence of nurses' professional experience in the detection of complications of the AVF (venous stenosis and steal syndrome). The study took place in eight hemodialysis centers between May and September of 2011 in the north of Portugal. Sample was constituted by registered nurses. The nurses involved in the experiment were divided in two groups: those who had more than 5 years of experience and those who had less than 5 years of experience. Ninety-two nurses participated in the study: 34 nurses had less than 5 years of professional experience and 58 had more than 5 years of professional experience. In the practices considered by nurses in the detection of venous stenosis, there were no differences observed between the groups (P > 0.05). In steal syndrome, there were no differences observed between the groups in the practices of the nurses in the detection of this complication of the AVF (P > 0.05). We concluded that professional experience does not influence the detection of venous stenosis and steal syndrome.

Abstract
The rapid growth of the World Wide Web has resulted in intricate Web sites, demanding enhanced user skills to find the required information and more sophisticated tools that are able to generate apt recommendations. Markov Chains have been widely used to generate next-page recommendations; however, accuracy of such models is limited. Herein, we propose the novel Semantic Variable Length Markov Chain Model (SVLMC) that combines the fields of Web Usage Mining and Semantic Web by enriching the Markov transition probability matrix with rich semantic information extracted from Web pages. We show that the method is able to enhance the prediction accuracy relatively to usage-based higher order Markov models and to semantic higher order Markov models based on ontology of concepts. In addition, the proposed model is able to handle the problem of ambiguous predictions. An extensive experimental evaluation was conducted on two real-world data sets and on one partially generated data set. The results show that the proposed model is able to achieve 15-20% better accuracy than the usage-based Markov model, 8-15% better than the semantic ontology Markov model and 7-12% better than semantic-pruned Selective Markov Model. In summary, the SVLMC is the first work proposing the integration of a rich set of detailed semantic information into higher order Web usage Markov models and experimental results reveal that the inclusion of detailed semantic data enhances the prediction ability of Markov models.

Abstract
Wireless visual sensor networks have been considered for a large set of monitoring applications related with surveillance, tracking and multipurpose visual monitoring. When sensors are deployed over a monitored field, permanent faults may happen during the network lifetime, reducing the monitoring quality or rendering parts or the entire network unavailable. In a different way from scalar sensor networks, camera-enabled sensors collect information following a directional sensing model, which changes the notions of vicinity and redundancy. Moreover, visual source nodes may have different relevancies for the applications, according to the monitoring requirements and cameras' poses. In this paper we discuss the most relevant availability issues related to wireless visual sensor networks, addressing availability evaluation and enhancement. Such discussions are valuable when designing, deploying and managing wireless visual sensor networks, bringing significant contributions to these networks.

Abstract
A dual-core fiber in which one of the cores is doped with Germanium and the other with Phosphorus is used as an in-line Mach-Zehnder (MZ) interferometer to perform high sensitivity strain and temperature sensing. Opposite sensitivities for high and low wavelength peaks were demonstrated when strain was applied. To our knowledge this is the first time that such behavior is demonstrated using this type of in-line MZ interferometer based on a dual-core fiber. A sensitivity of (78 +/- 2) pm/mu epsilon, between 0-950 mu epsilon and (1380 +/- 20) pm/degrees C between 45 and 80 degrees C is demonstrated. It was also demonstrated that it is possible to use this configuration for simultaneous measurement of strain and temperature and a matrix equation to calculate them was given.

Abstract
The extraction of morphometric features from images of biological structures is a crucial task for the study of several diseases. Particularly, concerning neuropathies, the state of the myelination process is vital for neuronal integrity and may be an indicator of the disease type and state. Few approaches exist to automatically analyse nerve morphometry and assist researchers in this time consuming task. The aim of this work is to develop an algorithm to detect axons and myelin contours in myelinated fibres of sciatic nerve images, thus allowing the automated assessment and quantification of myelination through the measurement of the g-ratio. The application of a directional gradient together with an active contour algorithm was able to effectively and accurately determine the degree of myelination in an imagiological dataset of sciatic nerves. It was obtained an average error of 1.80%, in comparison with the manual annotation performed by the specialist in all dataset.

Abstract
A practical electric distribution system is a nonlinear network, which is generally governed by a large number of differential and algebraic equations (DAE). For instance, the ordinary differential equations are defined by the dynamics of the generators (e.g., small-scale hydro generation units) and the loads, as well as distributed generation (DG) units and their controllers. Algebraic equalities are described by the distribution network current balance equations and internal static behaviors of passive devices. In this paper, a rigorous approach is used to convert a semi-explicit DAE system into an explicit ordinary differential equations (ODE) system. In this way, it is possible to apply the robust and well consolidated implicit integration methods to solve the semi-explicit DAE systems as for implicit ODE system. Two applications of the methods are presented. In the first example, the procedure solves the classical Robertson's problem, while in the second case study the dynamic behavior of a simple distribution system with a generator, an induction motor and an admittance load is reported. The results indicate that the proposed procedure is able to reach exactly the same results obtained by applying the classical solution procedure, without any further assumption about the nature of the results obtained.